Regulating nozzle for vaporizing burners



July. 3l, 194,5. l c. s. HoLM I REGULATING NOZZLE FOR VAPRIZNG BURNERS original Filed JanfzQ, 195:3v

Patented July 31, 1945 REGULATING NOZZLE FOR VAPORIZING BURNERS- v. Carl Bernhard Holm, Roslags-Nasby, Sweden Original application January 29, 1938, ,Serial No. 187,767. Divided and this application October 11, 1941, Serial No. 1937 414,692. In Sweden Julyv 3,

4 Claims. (Cl. 158-120) This is a division of. my earlier application led January 29, 1938, Ser. No. 187,767, now Patent No. 2,268,591, dated January 6, 1942, and the present invention relates to gasifying burners and in particular to gasifying burners for small furnaces or ovens, such as portable ovensl in which liquid fuel is used as a combustible.

'Ihe :object of my invention is to provide means for regulating the amount of gas passing through the fuel nozzle of the burner and for effectively cleansing the same.

The quantity of fuel passing through such nozzles is usually regulated by means of a conical needle which co-operates with a nozzle opening. This opening is formed so as to provide a flame of maximum size when the needle is wholly removed from the opening.

Known devices of this kind are subject to a number of drawbacks. 'I'he needle in a relatively short time becomes coated with a carbonaceous deposit so that subsequently the possibility of regulating the i'uel nozzle opening is considerably decreased since the outflowing vapor due to the coating on the needle changes its direction so that incomplete combustion with a sooty flame results. Moreover, with small valve openings, the nozzle acts asan expansion nozzle and the' velocity ofthe vapor is decreased to such extent that the amount of air required for combustion is no longer drawn by suction into the mixing chamber.

In the case of a. cooking stove or the like it is desirable that the same operate with a very small flame and that on the other hand the supply of heat necessary for vaporization is maintained. To obtain this minimum value the needle in prior devices has had to be adjusted with very great accuracy and the desired adiustment becomes practically impossible. Even if the burner after operating with a relatively full llame is adjustable to obtain a minimum flame the needle due to the temperature changes set up when decreasing the llame will be displaced relatively to the nozzle opening so that the correct position of the needle is not main- According to the present invention the regulating nozzle includes two or more needles cooperating with a corresponding number of nozzle o s and adapted to open or close said openings in succession on operation of a single control member which is externally accessible.

The regulating nozzle may comprise a plurality of nozzle openings co-operating with a corresponding number of needles, a common to said openings to produce closing and opening -valve 2|.

of different nozzle openings in succession.

The openings may be of different cross-sectional areas with the co-operating needles formed of corresponding cross-sections.

The invention will be hereinafter more fully p described with reference drawing. l

Fig. l is a. plan view of an apparatus constructed in accordance with my invention, part of the cover being broken away;

Fig. 2 shows to a larger scale a section of a detail of the fuel valve operating device; and

Fig. 3 shows to a larger scale a section of the fuel nozzle device.

Referring first to Fig. l, referencenumeral lil designates the casing of a portable oven or heating apparatus having an opening ll on its upper side. I2 is a reservoir for liquid fuel, such as petroleum, said reservoir being supported by the to the accompanying rear wall of the casing by means of a bracket i3.

provided for producing a super-atmospheric air pressure in the petroieum reservoir, said pressure being indicated by a pressure gauge I9. A-conduit 20 connects the reservoir l2 with a control By means of a conduit 22 the control valve 2l is connected to the lower portion of a vaporizer 23. Fuel gasied in said vaporizer is discharged through a controllable nozzle device 24 opposite which there is arranged a mixing chamber 25 forming part of a burner chamber generally denoted at 26.

For the purpose of starting the vaporizer I provide a' starting burner, cup 21 arranged to 4'receive starting fuel, such as alcohol, from a duit the measuring device Il canbe brought into communication with the air space of the fuel reservoir I2.

Having now described the general arrangement of different parts of my improved gasifying burner, I will now proceed with a more de- -tailed description of the main object of the invention.

The fuel valve for completely shutting off the gasiiied fuel flowing through the nozzle device is indicated at Il in Fig. 3. The stem Il of the fuel valve is enclosed, at a portion of its length, by a pipe 8C which has an opening l1' for the admission of gasiiied fuel into the nozzle chamber Il. The outer end of the valve stem "is connected by means of a right-handed thread portion Si to a screw 92 having left-handed threads. The screw l2 is threaded into a nut I3 secured to the front wall Il of the casing Il. The screw 92 has an elongation 0l in the form of a rectangularly shaped pin which engages a sleeve 96 secured to a turning button l1. Between the front wall $4 and a projection Il secured to the sleeve there are arranged abutments Il and lll to limi-t the turning movement of the buttonl1 within a range from the practically suitable minimum flame to the maximum flame. In order to extinguish the flame of the burner, the projection 9| is moved out of the path of the abutment $9 by drawing out the obutton l1 against the action of a helical spring IM inserted between the sleeve 86 ,and a plug |02 secured to the button and the pin 8l. Upon turning lthe button 81 the threaded portion Il of the stem l! will be displaced in axial ,direction in the screw I2, but it will be prevented from turning movements due to the fact that the threaded portions Il and 02 are provided with right-'and left-handed threads, respectively.-

The nozzle device is provided with two openings IIB and I" of which in the embodiment shown the first-named itl has a larger diameter than the other one. lThe valve stem II has an elongation |01 carrying a head ill which has secured thereto two cylindrical needles .llland H0, of which the one I" has substantially.

the same diameter as the larger opening ill, while the needle III has substantially the same diameter as the smaller opening III.

Having now particularly described and ascertained the nature of my said invention and in device, a fuel valve for what manner the same is to be performed, I declare that what I claim is:

l. A gasifying burner comprising, a fuel nozzle device, a fuel valve for shutting off the gasiied fuel, said nozzle device having a plurality of openings of different cross-sectional areas, and

said fuel valve for closing or means connected to opening in succession any desired number .of said nozzle openings.

2. A gasifying burner comprising. a fuel nozzle device, a fuel valve for shutting oil the gasified fuel, said nozzle device having two openings of different diameters, and twoy cleansing needles connected to said valve and having different lengths and being arranged to open or close said nomle openings in succession upon movement of the valve.

3. A gasifying burner comprising, a fuel nozzle device, a fuel valve for shutting off the gaslfled fuel, said nozzle device having two openings of different diameters, and two cleansing needles connected to said valve and having diiIerent lengths and being arranged to open or close said nozzle openings in succession upon movement of the valves, said cleansing needles being cylindrically shaped and having substantially the same diameters as the respective nozzle openings.

4. A gasifying burner comprising a fuel nozzle shutting ofi' gasifled fuel, a stem connected with said valve, means connected with said stem for moving said valve axially, said nozzle having a plurality of openings, and means connectedv with said valve for successively opening or closing said openings.

CARL BERNHARD HOLM.v 

